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by starpilot 2363 days ago
Thermoelectrics have terrible efficiency, that's why they're hardly used despite the fact that waste heat is literally everywhere. Your computer, your phone, your car engine, everywhere there is energy to be recovered. In theory, any heat-based powerplant could use them, but instead they all boil water and drive steam through turbines, which is much more efficient.
2 comments

Thermoelectrics you can order from a catalog have real world efficiency ~6%, which is on the order of what a well engineered practical Sterling engine will do for converting heat to electricity without any moving parts to wear out, exotic working fluids/seals, or ... complete lack of supply chain for any of the above. If this new material pans out it could be on the order of 24% efficient, which would be preposterously better than any heat engine you can fit in an Alaska cabin.

I hate the computer programmer weeb meme of suggesting a Sterling engine for every damn thing. None of you jokers suggesting this has ever built a real world heat engine, let alone attempted to engineer an efficient one from scratch, which is what you'd be doing in the case of log cabin Sterling engines. There are excellent reasons they're not commonly used, and less thermodynamically efficient external combustion engines (like steam) are used. The problems with making them work efficiently are immense.

>would be preposterously better than any heat engine you can fit in an Alaska cabin.

Or a cabin on Mars. Solar and nuclear would be used on Mars. For nuclear - with 20% efficiency i think it would allow to use simple RTG (Matt Damon style) instead of full blown nuclear reactor with working fluids, pumps, turbines, etc.

> Thermoelectrics have terrible efficiency

I agree with what you're saying, but the point is that the woodstove is running 24x7 in the winter, and the solar is very pool. Whatever energy I can get from the TECs is an order of magnitude more than I'll be making without them - i.e. zero.